Defy bad customer service

Mother bought a Defy stove at Game in Promenate in October when it was installed we have noticed the oven was not working, we went at Game store they call Defy technicians about the matter which they promised to come since 6th December 2019 the job was open by them, we've calling day in & out and been promising to send the technician until today we still waiting. Defy Appliances has bad customer service we still stucked with the stove that's new with oven that not working. Vey bad service